“If they don’t know, you can’t tell them”

Amb. Ryan Crocker and Gen. David Petraeus won’t set goalposts for Iraq. They won’t say when troops can start coming home in large numbers. They won’t define clear conditions for withdrawal. As they have been saying for nearly two days now, they will know success when they come upon it. This is kind of like Supreme Court Justice Potter Stewart’s claim about obscene pornography, “I know it when I see it,” or the Louis Armstrong admonition, “If you have to ask what jazz is, you’ll never know.”

Suffice it to say, the concept sounds a bit more comforting in the context of music or smut than, say, a $12 billion-per-month war that has killed more than 4,000 Americans. But beneath the vague language of the two witnesses, who continue to talk today in the House, there are the slightest hints that they acknowledge the conflict cannot go on forever with such mixed political progress on the ground.

Today, in the House Armed Services Committee, Petraeus was asked if he expected a resurge of troops after this summer, assuming conditions deteriorated. “I mean, that would be a pretty remote thought in my mind, for a variety of different reasons.” One of the reasons is that the military can’t really take much more strain.

Yesterday, Sen. Joe Biden got Petraeus to admit that America may be closer to drawing down troops below pre-surge levels than not, though he had to do it with a mathematical metaphor. “On a scale of 1 to 10, how far along are we on the progress scale before we get to the point we can significantly reduce American forces?” After dodging the question twice, Petraeus finally answered: “Well, I think we’re in a six or seven or somewhere along there, Senator.”

Not much, but it’s something. For more on yesterday’s hearings, I have a write up of the posturing of the presidential candidates here on Time.com.